Conservative Party Deputy Chairman James Cleverly told the Standard today: “Tom Watson should seriously consider distancing himself from Mr Mosley and returning the money.”

The pamphlet, discovered in historical archives in Manchester for a Union Movement candidate, includes the phrase “published by Max Mosley”.

Its discovery by the Daily Mail raises questions over evidence Mr Mosley gave under oath in a High Court trial when he successfully sued the News Of The World in 2008.

He insisted during the trial that it was “absolute nonsense” to suggest he had put out leaflets alleging that “coloured immigrants” brought diseases with them. However, when challenged by Channel 4 last night after a physical copy emerged, he said: “If it is genuine, it doesn’t reflect my views today.”

He also said it was “offensive” to suggest that he had perjured himself.

One of the warnings on the leaflet stated: “Tuberculosis, VD and other terrible diseases like leprosy are on the increase. Coloured immigration threatens your children’s health.”

Tory MP Andrew Bridgen, who campaigned against the BNP in Manchester, said Mr Watson should return the money until it is established who was responsible for the leaflet.

Mr Watson said: “The views expressed by Max as a young man are not the views he holds now.”

The Met police said today they have received no complaints or allegations relating to the evidence Mr Mosley gave on oath about the leaflet in 2008.